Self-driving?

I was driving around Seattle yesterday (Holman road just north of 85th while driving south in case you're playing along at home). I was going to make a right hand turn on 85th so I was in the right lane of the four-lane road. The vehicle in front on me was turning right before 85th.No problem.Until the Subaru I'm in decides to slam on the brakes.The collision avoidance is fucked.The road is curving to the left. The truck in front of me slows down to turn right. I'm turning left such that everything is copacetic.BRAKE!!!Coffee: spills. If someone would have been following too close behind: accident.To be overly clear, there was no chance that I would hit the truck. He had already pulled off onto a side street.Stuff like this makes me really hesitant about self-driving cars in general. I know what I'm capable of. But I don't know what the computer is capable of. I work with computers all day long... I don't much trust them (or the programmers) much.  :-/